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1.
Poult Sci ; 102(12): 103079, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37812870

RESUMO

Not all chickens access an outdoor range when the opportunity is provided. This may be related to the abrupt change in environments from the stable rearing conditions to the complexity of the outdoor range. We aimed to prepare chickens to range by increasing the complexity of the indoor environment early in life with the intention to encourage range use. Mixed sex Cobb500 chickens were allocated to 1 of 3 treatment groups: visual access (VA) treatment provided VA to the outdoor range from day old via transparent pop-hole covers; environmental complexity (EC) treatment provided an artificial haybale, fan with streamers and a solid vertical barrier; Control treatment was a representative conventional environment. Chickens were given access to the outdoor range at 21 d of age. Behavior in the home pen was assessed in wk 1, 2 and 5 and individual ranging behavior was monitored through radio frequency identification (RFID) technology. The VA chickens were more active compared to EC (P = 0.006) and Control (P = 0.007) chickens and spent more time foraging than control chickens (P = 0.036) during the first week of life. More VA chickens accessed the range area compared to EC chickens (P = 0.015). VA chickens accessed the range sooner after they were first provided access and spent more time on the range than EC and control chickens (P < 0.001). Mortality was lower in the VA treatment compared to EC (P = 0.024) and control group (P = 0.002). There was evidence that VA chickens weighed less than Control and EC chickens, however results were inconsistent between age and sex. Hence, providing meat chickens with VA to an outdoor range early in life increased activity in early life, decreased latency to first access the range and increased time on the range and lowered mortality. Future work should aim to understand the mechanism behind these changes in behavior to develop recommendations for producers to implement in commercial conditions.


Assuntos
Criação de Animais Domésticos , Galinhas , Animais , Criação de Animais Domésticos/métodos , Carne/análise , Abrigo para Animais
2.
J Frailty Aging ; 10(4): 343-349, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34549249

RESUMO

BACKGROUND: The risks of intensive blood glucose lowering may outweigh the benefits in vulnerable older people. OBJECTIVES: Our primary aim was to determine whether age, frailty, or dementia predict discharge treatment types for patients with type 2 diabetes (T2D) and related complications. Secondly, we aimed to determine the association between prior hypoglycemia and discharge treatment types. DESIGN, SETTING AND PARTICIPANTS: We conducted a cohort study involving 3,067 patients aged 65-99 years with T2D and related complications, discharged from Melbourne's Eastern Health Hospital Network between 2012 and 2016. MEASUREMENTS: Multinomial logistic regression was used to estimate odds ratios (ORs) with 95% confidence intervals (CI) for the association between age, frailty, dementia and hypoglycemia, and being prescribed insulin-only, non-insulin glucose-lowering drugs (GLDs) or combined insulin and non-insulin GLDs compared to no GLD. International Classification of Diseases-10 codes were used to identify dementia status and prior hypoglycemia; frailty was quantified using the Hospital Frailty Risk Score. RESULTS: Insulin-only, non-insulin GLDs, combined insulin and non-insulin GLDs, and no GLDs were prescribed to 19%, 39%, 20%, and 23% of patients, respectively. Patients >80 years were less likely than patients aged 65-80 to be prescribed any of the GLD therapies, (eg. non-insulin GLDs [OR 0.67; 95%CI 0.55-0.82]), compared to no GLD. Similarly, high vs. low frailty scores were associated with not being prescribed any of the three GLD therapies, (eg. non-insulin GLDs [OR 0.63; 95%CI 0.45-0.87]). However, dementia was not associated with discharge prescribing of GLD therapies. Patients with a hypoglycemia-related admission were more likely than those not hospitalized with hypoglycemia to receive insulin-only (OR 4.28; 95%CI 2.89-6.31). CONCLUSIONS: Clinicians consider age and frailty when tailoring diabetes treatment regimens for patients discharged from hospital with T2D and related complications. There is scope to optimize prescribing for patients with dementia and for those admitted with hypoglycemia.


Assuntos
Demência , Diabetes Mellitus Tipo 2 , Fragilidade , Idoso , Estudos de Coortes , Demência/tratamento farmacológico , Demência/epidemiologia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/epidemiologia , Fragilidade/epidemiologia , Hospitais , Humanos , Alta do Paciente
3.
Expert Rev Gastroenterol Hepatol ; 11(6): 593-601, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28276815

RESUMO

BACKGROUND: We investigated the real-world effectiveness of interferon-free regimens for the treatment of patients with compensated cirrhosis infected with hepatitis C virus (HCV). METHOD: Using the Irish national HCV treatment registry, the effectiveness and safety of interferon-free regimens for HCV-infected patients treated between April 2015 and August 2016, was determined. RESULTS: A SVR12 was achieved in 86% of subjects treated with sofosbuvir/ledipasvir ± ribavirin (SOF/LDV±RBV), 93% treated with paritaprevir, ombitasvir and ritonavir combined with dasabuvir ± ribavirin (3D±RBV) and 89% treated with sofosbuvir/daclatasvir ± ribavirin (SOF/DCV±RBV). The discontinuation rate was 5% and the on-treatment mortality rate was 1%. CONCLUSION: The availability of interferon-free regimens represents a significant breakthrough for the treatment of HCV infection. Treatments options, with high SVR12 rates, are now available for patients with compensated cirrhosis who were unsuitable for treatment with interferon-based regimens. Data obtained from studies conducted in real world practice provide robust information fundamental for input into future economic evaluations for agents used for the treatment of HCV infection.


Assuntos
Antivirais/uso terapêutico , Benzimidazóis/uso terapêutico , Fluorenos/uso terapêutico , Acessibilidade aos Serviços de Saúde , Hepacivirus/efeitos dos fármacos , Hepatite C/tratamento farmacológico , Cirrose Hepática/tratamento farmacológico , Ribavirina/uso terapêutico , Uridina Monofosfato/análogos & derivados , Adulto , Antivirais/efeitos adversos , Benzimidazóis/efeitos adversos , Quimioterapia Combinada , Feminino , Fluorenos/efeitos adversos , Genótipo , Hepacivirus/genética , Hepacivirus/crescimento & desenvolvimento , Hepatite C/complicações , Hepatite C/diagnóstico , Hepatite C/mortalidade , Humanos , Irlanda , Cirrose Hepática/diagnóstico , Cirrose Hepática/mortalidade , Cirrose Hepática/virologia , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Avaliação de Programas e Projetos de Saúde , Estudos Prospectivos , Sistema de Registros , Ribavirina/efeitos adversos , Sofosbuvir , Resposta Viral Sustentada , Fatores de Tempo , Resultado do Tratamento , Uridina Monofosfato/efeitos adversos , Uridina Monofosfato/uso terapêutico
4.
Ir Med J ; 109(8): 451, 2016 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-28124851

RESUMO

Hepatitis E virus (HEV) is a single stranded RNA virus causing infection worldwide. In developing countries HEV genotypes 1 and 2 spread faeco-orally via water. Recently, infections with HEV have been detected in Europe and North America in patients with no travel history. These are food-borne HEV genotypes 3 and 4, a pig-associated zoonosis. Most infections are asymptomatic but morbidity and chronic infection may occur with prior liver disease or immunosuppression. International seroprevalence rates vary and with improved diagnostics have increased. To determine the current prevalence in this region we studied anonymised serum samples submitted in 2015 for routine testing. We detected anti-HEV IgG in 16/198 (8%) individuals, highest rate in 40-59 year olds (43.8%). This is higher than reported for the same region in 1995 (0.4%) using a previous generation assay. This study provides evidence of HEV circulation in Ireland and reinforces the need for ongoing surveillance.


Assuntos
Vírus da Hepatite E/imunologia , Hepatite E/epidemiologia , Imunoglobulina G/sangue , Animais , Europa (Continente)/epidemiologia , Doenças Transmitidas por Alimentos/epidemiologia , Doenças Transmitidas por Alimentos/virologia , Genótipo , Vírus da Hepatite E/genética , Humanos , Irlanda/epidemiologia , Estudos Soroepidemiológicos
5.
Bone Marrow Transplant ; 47(7): 924-33, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22002488

RESUMO

As the threshold nucleated cell dose for one-unit umbilical cord blood (UCB) in adults has not to date been firmly established, we prospectively compared one- vs two-unit UCB transplantation after reduced intensity conditioning (RIC) in adult patients with hematological malignancies. Study design specified one-UCB unit if the cryopreserved total nucleated cell (TNC) dose was 2.5 × 10(7)/kg recipient weight, otherwise two units matched at minima of 4/6 HLA loci to the patient and 3/6 to each other were infused. A total of 27 patients received one unit; 23 patients received two units. Median time to ANC >500/µL was 24 days (95% confidence interval 22-28 days), 25 days for one unit and 23 days for two units (P=0.99). At day 100, ANC >500/µL was 88.4 and 91.3% in the one- and two-unit groups (P=0.99), respectively. Three-year EFS was 28.6% and 39.1% in the one- and two-unit groups (P=0.71), respectively. Infusion of two units was associated with a significantly lower relapse risk, 30.4% vs 59.3% (P=0.045). Infused cell doses (TNC, CD3(+), CD34(+) and CD56(+)CD3(neg)) did not impact on engraftment, OS or EFS. Taken together, one-unit UCB transplantation with a threshold cell dose 2.5 × 10(7)/kg recipient weight after RIC is a viable option for adults, although infusion of two units confers a lower relapse incidence.


Assuntos
Transplante de Células-Tronco de Sangue do Cordão Umbilical/métodos , Neoplasias Hematológicas/terapia , Condicionamento Pré-Transplante/métodos , Adulto , Idoso , Transplante de Células-Tronco de Sangue do Cordão Umbilical/efeitos adversos , Feminino , Doença Enxerto-Hospedeiro/etiologia , Teste de Histocompatibilidade , Humanos , Masculino , Pessoa de Meia-Idade , Neutrófilos/patologia , Estudos Prospectivos , Condicionamento Pré-Transplante/efeitos adversos , Resultado do Tratamento , Adulto Jovem
6.
Clin Exp Allergy ; 41(12): 1679-89, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21883538

RESUMO

Adverse reactions to drugs are increasingly being recognized as important contributions to disease in their own right as well as impediments to the best treatment of various conditions, including infectious, autoimmune, and neoplastic maladies. Rapid drug desensitization (RDD) is an effective mechanism for safely administering important medications while minimizing or entirely circumventing such adverse reactions in sensitized patients. We reviewed the literature on RDD in the last 10 years, including our experience from the Brigham and Women's Hospital Desensitization Program with hundreds of patients desensitized to a broad variety of drugs. RDD in our programme has been uniformly successful in patients with hypersensitivity reactions to antibiotics, chemotherapeutics, and monoclonal antibodies. Any reactions that occur during desensitization are generally much less severe than the initial hypersensitivity reaction to the drug, and patients have received the full dose of the desired medication 99.9% of the time out of (796) desensitizations. To date, there have been no fatalities. RDD is a safe and highly effective method for treating sensitized patients with the optimal pharmacologic agents. Its use should be expanded, but because patient safety is paramount, protocols must be created, reviewed, and overseen by allergist-immunologists with special training and experience in modern techniques of desensitization.


Assuntos
Dessensibilização Imunológica/métodos , Hipersensibilidade a Drogas/terapia , Antibacterianos/efeitos adversos , Antibacterianos/imunologia , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais/imunologia , Antineoplásicos/efeitos adversos , Antineoplásicos/imunologia , Hipersensibilidade a Drogas/imunologia , Humanos , Compostos Organoplatínicos/efeitos adversos , Compostos Organoplatínicos/imunologia , Taxoides/efeitos adversos , Taxoides/imunologia
7.
Leukemia ; 22(12): 2201-7, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18769450

RESUMO

On activation, umbilical cord blood (UCB) CD4(+) T cells demonstrate reduced expression of tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma), whereas maintaining equivalent interleukin-2 (IL-2) levels, as compared with adult peripheral blood (PB) CD4(+) T cells. Nuclear factor of activated T cells (NFAT1) protein, a transcription factor known to regulate the expression of IL-2, TNF-alpha and IFN-gamma, is reduced in resting and activated UCB CD4(+) T cells. In contrast, expression of Broad-complex-Tramtrack-Bric-a-Brac and Cap'n'collar homology 1 bZip transcription factor 2 (BACH2) was shown by gene array analyses to be increased in UCB CD4(+) T cells and was validated by qRT-PCR. Using chromatin immunoprecipitation, BACH2 was shown binding to the human IL-2 proximal promoter. Knockdown experiments of BACH2 by transient transfection of UCB CD4(+) T cells with BACH2 siRNA resulted in significant reductions in stimulated IL-2 production. Decreased IL-2 gene transcription in UCB CD4(+) T cells transfected with BACH2 siRNA was confirmed by a human IL-2 luciferase assay. In summary, BACH2 maintains IL-2 expression in UCB CD4(+) T cells at levels equivalent to adult PB CD4(+) T cells despite reduced NFAT1 protein expression. Thus, BACH2 expression is necessary to maintain IL-2 production when NFAT1 protein is reduced, potentially impacting UCB graft CD4(+) T-cell allogeneic responses.


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Linfócitos T CD4-Positivos/fisiologia , Sangue Fetal/citologia , Interleucina-2/genética , Sequência de Bases , Fatores de Transcrição de Zíper de Leucina Básica/genética , Linfócitos T CD4-Positivos/citologia , Linhagem Celular Tumoral , Expressão Gênica/imunologia , Genes Reporter , Humanos , Tolerância Imunológica/genética , Tolerância Imunológica/fisiologia , Fatores de Transcrição NFATC/metabolismo , Regiões Promotoras Genéticas/imunologia , Regiões Promotoras Genéticas/fisiologia , RNA Mensageiro/metabolismo , RNA Interferente Pequeno , Células Th1/citologia , Células Th1/fisiologia , Transfecção , Cordão Umbilical
9.
J Viral Hepat ; 14(1): 2-10, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17212638

RESUMO

Soon after the discovery of the hepatitis C virus (HCV), attention turned to the development of models whereby replication of the virus could be investigated. Among the HCV replication models developed, the HCV RNA replicon model and the newly discovered infectious cell culture systems have had an immediate impact on the study of HCV replication, and will continue to lead to important advances in our understanding of HCV replication. The aim of this study is to deal with developments in HCV replication models in a chronological order from the early 1990s to the recent infectious HCV cell culture systems.


Assuntos
Hepacivirus/fisiologia , Replicação Viral/fisiologia , Animais , Genoma Viral , Hepacivirus/genética , Hepatite C/virologia , Humanos , Pan troglodytes , RNA Viral/genética , Replicon/genética , Replicon/fisiologia , Vírion/genética , Vírion/fisiologia , Replicação Viral/genética
10.
J Viral Hepat ; 12(6): 594-603, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16255760

RESUMO

In hepatitis C virus (HCV) infection, serum viral load is important in the prediction of therapeutic efficacy. However, factors that affect the viral load remain poorly understood. To identify viral genomic elements responsible for the viral load, we investigated samples from a population of Irish women who were iatrogenically infected from a single HCV source by administration of HCV 1b-contaminated anti-D immune globulin between 1977 and 1978 (Kenny-Walsh, N Engl J Med 1999; 340: 1228). About 15 patients were divided into two groups, viral load increasing group (11 patients) and decreasing group (4 patients). Pairs of sera were collected from each patient at interval between 1.1 and 5.8 years. Full-length sequences of HCV genome were determined, and analyzed for changes in each patient. Sliding window analysis showed that the decreasing group had significantly higher mutation rates in a short segment of NS5B region that may affect the activity of RNA-dependent RNA polymerase. By comparing each coding regions, significantly higher mutation numbers were accumulated in NS5A region in the increasing group than the decreasing group (0.92 vs 0.16 nucleotides/site/year, P = 0.021). The mutation in certain positions of the HCV genome may be determinant factors of the viral load in a relatively homogeneous patient population.


Assuntos
Contaminação de Medicamentos , Evolução Molecular , Genoma Viral , Hepacivirus/genética , Fatores Imunológicos/administração & dosagem , Imunoglobulina rho(D)/administração & dosagem , Carga Viral , Sequência de Aminoácidos , Feminino , Hepacivirus/fisiologia , Hepatite C/imunologia , Hepatite C/terapia , Hepatite C/virologia , Humanos , Fatores Imunológicos/uso terapêutico , Irlanda , Dados de Sequência Molecular , Mutação , Filogenia , Imunoglobulina rho(D)/uso terapêutico , Análise de Sequência de DNA
11.
J Virol Methods ; 123(2): 115-24, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15620392

RESUMO

Hepatitis C virus (HCV) genotype is a predictor of response, and guides the duration of antiviral therapy. However, with the exception of HCV genotype 1a, 1b and 2a, a limited number of clones from other genotypes exist. Here we report the optimization of long RT-PCR to generate three overlapping amplicons that span the near full length HCV genome from a panel of HCV genotypes (1a, 1b, 2a, 2b, 3a, 4a, 5a). Assembly-PCR (As-PCR) was used to construct near full-length cDNA clones (assemblicons) for each genotype. The optimization of the long RT-PCR on genotype 1a and 1b indicated that QIAamp Viral RNA kit (Qiagen, UK), Expand RT and Expand Long Template PCR system (Roche, UK), were the most efficient in producing the requisite three overlapping amplicons and assemblicons for each genotype. The genotype of each assemblicon was confirmed. Assemblicon generation was only possible when the overlapping amplicons were biotinylated. As-PCR obviated the need for time consuming ligations and cloning. The use of three overlapping amplicons in the construction of HCV assemblicons minimised the chimeric nature of the resultant clone. As-PCR may prove a methodological avenue through which a larger panel of consensus HCV clones could be made available for HCV in vitro investigation.


Assuntos
Genótipo , Hepacivirus/genética , Hepatite C/virologia , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , DNA Complementar/análise , DNA Viral , Hepacivirus/classificação , Kit de Reagentes para Diagnóstico
12.
J Viral Hepat ; 11(2): 108-14, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-14996344

RESUMO

Since the first report of genetically heterogeneous, or quasispecies, populations of RNA viruses, the genetic heterogeneity of the RNA genomes of major viral pathogens has been extensively studied. These studies aim to provide insights into the evolutionary pressures that act upon viruses, in order to define windows where anti-viral therapies will be most effective, to take prognostic values from viral genetic distributions at a given time, and to aid the development of novel therapeutic compounds that may tilt viral replication towards information loss. Many methodologies are employed to analyse genetic distributions of a virus in a given sample, but all involve the generation, and subsequent analysis, of the sequence information contained in a reverse-transcription-polymerase chain reaction (RT-PCR) product. Despite the fact that the aim of these RT-PCRs is to obtain sequence information from viral genomes, their application to this task is approached without adequate consideration of this end-goal. The establishment of an RT-PCR for a specific viral target genome generally proceeds in the same fashion as one would apply to establishing a PCR to determine the presence or absence of a specific target sequence in a given sample. However, it is becoming increasingly apparent that RT-PCR products generated by amplification with the ubiquitous thermostable DNA polymerase Taq, coupled with standard cloning and sequencing methodologies, has the potential to yield inaccurate and misleading data as pertains to the information content of populations of RNA viral genomes. This review discusses varying approaches employed to analyse heterogeneous populations of hepatitis C virus RNA genomes.


Assuntos
Variação Genética , Genoma Viral , Vírus de RNA/classificação , Vírus de RNA/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Taq Polimerase/metabolismo , Pareamento Incorreto de Bases , Clonagem Molecular , Vírus de RNA/química , Análise de Sequência de DNA
13.
Enzyme Microb Technol ; 28(7-8): 682-688, 2001 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-11339953

RESUMO

A recombinant Rhizobium meliloti beta-galactosidase was purified to homogeneity from an Escherichia coli expression system. The gene for the enzyme was cloned into a pKK223-3 plasmid which was then used to transform E. coli JM109 cells. The enzyme was purified 35-fold with a yield of 34% by a combination of DEAE-cellulose (pH 8.0) and two sequential Mono Q steps (at pH 8.0 and 6.0, respectively). The purified enzyme had an apparent molecular mass of 174 kDa and a subunit molecular weight of 88 kDa, indicating that it is a dimer. It was active with both synthetic substrates p-nitrophenyl beta-D-galactopyranoside (PNPG) and o-nitrophenyl beta-D-galactopyranoside (ONPG) with K(m)(PNPG) and K(m)(ONPG) of 1 mM at 25 degrees C. The k(cat)/K(m) ratios for both substrates were approximately 70 mM(-1) sec(-1), indicating no clear preference for either PNPG or ONPG, unlike E. coli beta-galactosidase. After non-denaturing electrophoresis, active beta-galactosidase bands were identified using 5-bromo-4-chloro-3-indolyl beta-D-galactopyranoside (X-gal) or 6-bromo-2-naphthyl beta-D-galactopyranoside (BNG) and diazo blue B.

14.
Anal Biochem ; 289(2): 137-46, 2001 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-11161307

RESUMO

The hepatitis C virus (HCV) is known to circulate in vivo as a quasispecies, a population of closely related, but genetically nonidentical virions. HCV reverse transcriptase (RT)-(nested) polymerase chain reaction (PCR) strategies are used to study quasispecies diversity at certain important viral genetic loci, predominantly at hypervariable region 1 (HVR 1) of the E2 envelope gene, and the interferon sensitivity determining region (ISDR) of the nonstructural 5a (NS5a) gene. We have found that the choice of DNA polymerase employed in viral PCR has effects on the inferred viral diversity at two distinct loci on the HCV genome. Nested HVR 1 and ISDR PCR was performed with both proofreading (Pwo) and nonproofreading (Taq) DNA polymerases on identical cDNA derived from three separate HCV-positive sera. Amplicons were cloned and sequences determined for 18-20 individual clones per sample. Quasispecies diversity determined from HVR 1 and ISDR PCR products showed that there was a marked effect on the inferred diversity depending on which DNA polymerase was employed in the PCR. The deduced amino acid sequences of the major variants within each specimen were identical for both Taq and Pwo DNA polymerase-mediated PCRs. However, a greater number of minor variants were observed in the Taq-generated amplicons, 80% of which were not observed in the Pwo-generated amplicons. Primer editing in the Pwo-generated amplicons was observed in 19% (20/104) of clones examined. Single-strand conformational polymorphism analysis of multiple replicates of each amplicon revealed good intra-PCR reproducibility in terms of genetic heterogeneity, and that as such the observations were not due to poor PCR reproducibility. The use of nonproofreading DNA polymerases to assess viral diversity can yield an incorrect quasispecies spectrum and affect RT-PCR assay performance. The contribution of Taq-induced errors and lack of adaptability of primers to potentially heterologous template-binding sites indicate that proofreading DNA polymerases should be the enzyme of choice in these systems.


Assuntos
DNA Polimerase Dirigida por DNA/metabolismo , Variação Genética , Hepacivirus/genética , Sequência de Aminoácidos , Sequência de Bases , Clonagem Molecular , DNA Complementar/metabolismo , Genoma Viral , Genótipo , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Polimorfismo Genético , Polimorfismo Conformacional de Fita Simples , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido Nucleico , Especificidade da Espécie , Taq Polimerase/metabolismo , Transcrição Gênica
15.
J Clin Virol ; 20(3): 163-71, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11166666

RESUMO

BACKGROUND: The increasing clinical application of viral load assays for monitoring viral infections has been an incentive for the development of standardized tests for the hepatitis C virus. OBJECTIVE: To develop a simple model for the prediction of baseline viral load in individuals infected with the hepatitis C virus. METHODOLOGY: Viral load quantification of each patient's first sample was assessed by RT-PCR-ELISA using the Roche MONITOR assay in triplicate. Genotype of the infecting virus was identified by reverse line probe hybridization, using amplicons resulting from the qualitative HCV Roche AMPLICOR assay. RESULTS: Retrospective evaluation of first quantitative values suggested that 82.4% (n=168/204) of individuals had a viral load between 4.3 and 6.7 log(10) viral copies per ml. A few patients (3.4%; n=7/204) have a serum viremia less than the lower limit of the linear range of the RT-PCR assay. Subsequent, prospective evaluation of hepatitis C viral load of all new patients using a model based on the dynamic range of viral load in the retrospective group correctly predicted the dynamic range in 75.9% (n=33/54). CONCLUSION: The dynamic range of hepatitis C viremia extends beyond the linear range of the Roche MONITOR assay. Accurate determination of serum viremia is substantially improved by dilution of specimens prior to quantification.


Assuntos
Hepacivirus/genética , Hepatite C/virologia , DNA Viral/análise , Ensaio de Imunoadsorção Enzimática , Feminino , Genótipo , Humanos , Masculino , Estudos Prospectivos , RNA Viral/sangue , Kit de Reagentes para Diagnóstico , Estudos Retrospectivos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Carga Viral , Viremia/virologia
16.
Am J Gastroenterol ; 96(12): 3384-9, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11774953

RESUMO

OBJECTIVE: Liver biopsy is regarded as the gold standard for assessing disease activity in chronic hepatitis C, but sampling error is a potential limitation. Whether sampling variability applies equally to viral load assessment as it does to histology is uncertain. To examine this, we compared viral load between right- and left-lobe biopsy specimens from patients infected with hepatitis C virus (HCV). METHODS: Bilobe biopsies were taken from 16 patients who were serum positive for HCV RNA by reverse transcription-polymerase chain reaction. Genotype was identified by reverse line probe hybridization. There was an absence of competing risk factors for infectious and other liver diseases in this patient group. Histology and hepatic viral load were assessed blindly. None of the patients had received antiviral therapy at the time of study. RESULTS: Detection of HCV in right and left lobes was concordant with serum positivity in all cases. The viral load between lobes was highly correlated (p = 0.0003, r = 0.79). In contrast, the histological activity indices of inflammation and fibrosis/cirrhosis were poorly correlated between lobes (p = 0.038, r = 0.60, and p = 0.098, r = 0.50, respectively). CONCLUSION: Hepatic viral load variability does not suffer from the same degree of heterogeneity of sampling variability as does histology.


Assuntos
Hepacivirus/isolamento & purificação , Hepatite C Crônica/virologia , Fígado/virologia , Adulto , Idoso , Sangue/virologia , Feminino , Fibrose , Hepatite C Crônica/sangue , Hepatite C Crônica/patologia , Humanos , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Carga Viral
17.
Hepatology ; 33(1): 224-30, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11124840

RESUMO

The aim of this study was to investigate the relationship between human leukocyte antigen (HLA) class II genes and the natural fluctuations in hepatitis C viral load in a homogeneous patient population. The study group consisted of 57 viremic (hepatitis C virus [HCV] 1b) women for whom HLA class II DRB1 and DQB1 haplotyping, virologic, histologic, and biochemical markers of disease activity were available. All patients were infected with HCV 1b from the same source of hepatitis C-contaminated anti-D immunoglobulin during the period from May 1977 to November 1978. The mean slope of change of viral load was 0.34 (SD +/- 0.73) log(10) viral copies/mL/year, which is significantly different from zero, P < 10(-9). Analysis of the relationship between the slope of change of viral load and HLA class II haplotype indicated a significantly different slope of change of viral load between the alleles of (1) DRB1(*)15 and DRB1(*)0701, and (2) DQB1(*)0602 and DQB1(*)0201, P(c) =.036 and P(c) =.026 after Bonferroni correction for multiple comparisons, respectively. Significant differences for grade and stage of disease at liver biopsy were observed for DQB1(*)0501 and DQB1(*)0201 alleles; P =.019, r(s) =.64, and P =.047, r(s) =.57, respectively. In addition, significant differences in stage of disease were found to exist between DRB1(*)13 and DRB1(*)0701, P =.031, r(s) = -.71. Our results define an association between the slope of change of viral load and HLA class II haplotype in patients infected with genotype 1b of HCV. This suggests a role for host immunogenetic factors in HCV infection in this homogeneous group.


Assuntos
Hepatite C/genética , Hepatite C/virologia , Antígenos de Histocompatibilidade Classe II/genética , Adulto , Alelos , Estudos de Coortes , Feminino , Antígenos HLA-DQ/genética , Cadeias beta de HLA-DQ , Antígenos HLA-DR/genética , Cadeias HLA-DRB1 , Haplótipos , Hepatite C/imunologia , Humanos , Carga Viral , Viremia/genética , Viremia/imunologia , Viremia/virologia
18.
QJM ; 93(9): 597-601, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10984554

RESUMO

A large cohort of rhesus-negative women in Ireland were inadvertently infected with hepatitis C virus following exposure to contaminated anti-D immunoglobulin in 1977-8. This major iatrogenic episode was discovered in 1994. We studied 36 women who had been infected after their first pregnancy, and compared them to an age- and parity-matched control group of rhesus-positive women. The presence of hepatitis C antibody was confirmed in all 36 by enzyme-linked immunosorbent assay and by recombinant immunoblot assay, while 26 (72%) of the cohort were HCV-RNA-positive (type 1b) on PCR testing. In the 20 years post-infection, all members of the study group had at least one pregnancy, and mean parity was 3.5. They had a total of 100 pregnancies and 85 of these went to term. There were four premature births, one being a twin pregnancy, and 11 spontaneous miscarriages. One miscarriage occurred in the pregnancy following HCV infection. There were two neonatal deaths due to severe congenital abnormalities in the PCR-positive women. Of the children born to HCV-RNA positive mothers, only one (2.3%) tested positive for the virus. Significant portal fibrosis on liver biopsy was confined to HCV-RNA-positive mothers apart from one single exception in the antibody-positive HCV-RNA-negative group. Comparison with the control group showed no increase in spontaneous miscarriage rate, and no significant difference in obstetric complications; birth weights were similar for the two groups.


Assuntos
Hepatite C Crônica , Doença Iatrogênica , Complicações Infecciosas na Gravidez , Adulto , Estudos de Casos e Controles , Anormalidades Congênitas , Feminino , Morte Fetal , Fibrose , Hepacivirus/genética , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Transmissão Vertical de Doenças Infecciosas , Fígado/patologia , Paridade , Gravidez , RNA Viral/sangue , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Isoimunização Rh/terapia , Imunoglobulina rho(D)/administração & dosagem , Gêmeos
19.
Hepatology ; 31(6): 1334-7, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10827160

RESUMO

The aim of this study was to investigate the possibility of a significant relationship between human leukocyte antigen (HLA) class II and the clearance of hepatitis C virus (HCV). The study group consisted of 156 Irish women who iatrogenically received HCV 1b-contaminated Anti-D immunoglobulin between May 1977 and November 1978. Thus, the study population was homogeneous in terms of gender, source of infection, and ethnicity. On Screening in 1994, all individuals were anti-HCV antibody positive by recombinant immunoblot assay, while 46% (n = 72) of the group were HCV-positive by reverse transcriptase-polymerase chain reaction (RT-PCR). HLA DRB1 and DQB1 status was molecularly defined by high resolution reverse line probe hybridization methodology. Clearance of HCV 1b was found to be associated with DRB1*01. However, this association was lost after Bonferroni correction for multiple comparisons. Extended haplotype analysis between specific DRB1 and DQB1 allelic combinations identified a significant reduction in the frequency of DQB1*0501 in the presence of DRB1*0701 in the persistently infected individuals in the study group (P <.05). No associations with either viral clearance or persistence were found at the DQB1 locus. Our results suggest that HLA DRB1*01 appears to contribute to the spontaneous resolution of a primary HCV infection in the Irish population. The presence of DRB1*0701 in the absence of DQB1*0501 possibly reflects an influence of this allele in persistence of HCV infection. Defined and homogeneous patient populations offer the best opportunity to illuminate previously disguised immunogenetic factors important in the clearance of HCV 1b.


Assuntos
Hepacivirus/classificação , Hepacivirus/isolamento & purificação , Hepatite C/imunologia , Hepatite C/virologia , Antígenos de Histocompatibilidade Classe II/análise , Alelos , Feminino , Seguimentos , Genótipo , Antígenos HLA-DQ/análise , Cadeias beta de HLA-DQ , Antígenos HLA-DR/análise , Cadeias HLA-DRB1 , Hepacivirus/genética , Antígenos de Histocompatibilidade Classe II/genética , Homozigoto , Humanos , Doença Iatrogênica , RNA Viral/análise
20.
Hepatology ; 31(1): 225-9, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10613750

RESUMO

The aim of this study was to determine the variation in hepatitis C viral load over an extended period of patient follow up. Serum samples were collected from 49 female individuals who were identified as having been infected from the same source of hepatitis C-contaminated anti-D immunoglobulin during the period from 1977 (May) to 1978 (November). All patients attended the hepatitis C clinic at Cork University Hospital, Cork, Ireland. The study group was homogeneous with respect to gender, hepatitis C virus (HCV) genotype (1b), and duration of infection. None of the patients had received antiviral therapy at the time of completion of study. Viral load quantifications were assessed using the Roche Monitor (F. Hoffmann-La Roche, Ltd., Basel, Switzerland) assay. The mean age of the study group at time of infection was 30.3 years (SD +/- 6.1) with a range from 18.5 to 43 years. The mean time of follow-up was 4. 1 years (SD +/- 1.0) with a range from 1.2 to 5 years. The mean rate of change of viral load per year was 0.23 log(10) viral copies per mL serum for the study group (SD +/- 0.19) with a range of -0.18 to 0.78 that was significantly different from zero, P < 10(-10). The rate of change of viral load per year was negatively correlated with viral load at first determination, r = -.35, P =.01. Age at infection did not correlate with the slope of change of viral load, P =.10. In conclusion, most women infected with HCV 1b will have an increase in viral load over time but a few patients who acquire infection early in adult life will show a decrease in viral load.


Assuntos
Hepatite C/virologia , Carga Viral , Adolescente , Adulto , Contaminação de Medicamentos , Feminino , Hepatite C/transmissão , Humanos , Irlanda , Estudos Prospectivos , Imunoglobulina rho(D) , Fatores de Tempo
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